1#include "cache.h"
2
3const char *prefix_path(const char *prefix, int len, const char *path)
4{
5 const char *orig = path;
6 for (;;) {
7 char c;
8 if (*path != '.')
9 break;
10 c = path[1];
11 /* "." */
12 if (!c) {
13 path++;
14 break;
15 }
16 /* "./" */
17 if (c == '/') {
18 path += 2;
19 continue;
20 }
21 if (c != '.')
22 break;
23 c = path[2];
24 if (!c)
25 path += 2;
26 else if (c == '/')
27 path += 3;
28 else
29 break;
30 /* ".." and "../" */
31 /* Remove last component of the prefix */
32 do {
33 if (!len)
34 die("'%s' is outside repository", orig);
35 len--;
36 } while (len && prefix[len-1] != '/');
37 continue;
38 }
39 if (len) {
40 int speclen = strlen(path);
41 char *n = xmalloc(speclen + len + 1);
42
43 memcpy(n, prefix, len);
44 memcpy(n + len, path, speclen+1);
45 path = n;
46 }
47 return path;
48}
49
50/*
51 * Unlike prefix_path, this should be used if the named file does
52 * not have to interact with index entry; i.e. name of a random file
53 * on the filesystem.
54 */
55const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
56{
57 static char path[PATH_MAX];
58 if (!pfx || !*pfx || arg[0] == '/')
59 return arg;
60 memcpy(path, pfx, pfx_len);
61 strcpy(path + pfx_len, arg);
62 return path;
63}
64
65/*
66 * Verify a filename that we got as an argument for a pathspec
67 * entry. Note that a filename that begins with "-" never verifies
68 * as true, because even if such a filename were to exist, we want
69 * it to be preceded by the "--" marker (or we want the user to
70 * use a format like "./-filename")
71 */
72void verify_filename(const char *prefix, const char *arg)
73{
74 const char *name;
75 struct stat st;
76
77 if (*arg == '-')
78 die("bad flag '%s' used after filename", arg);
79 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
80 if (!lstat(name, &st))
81 return;
82 if (errno == ENOENT)
83 die("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
84 "Use '--' to separate paths from revisions", arg);
85 die("'%s': %s", arg, strerror(errno));
86}
87
88/*
89 * Opposite of the above: the command line did not have -- marker
90 * and we parsed the arg as a refname. It should not be interpretable
91 * as a filename.
92 */
93void verify_non_filename(const char *prefix, const char *arg)
94{
95 const char *name;
96 struct stat st;
97
98 if (!is_inside_work_tree() || is_inside_git_dir())
99 return;
100 if (*arg == '-')
101 return; /* flag */
102 name = prefix ? prefix_filename(prefix, strlen(prefix), arg) : arg;
103 if (!lstat(name, &st))
104 die("ambiguous argument '%s': both revision and filename\n"
105 "Use '--' to separate filenames from revisions", arg);
106 if (errno != ENOENT)
107 die("'%s': %s", arg, strerror(errno));
108}
109
110const char **get_pathspec(const char *prefix, const char **pathspec)
111{
112 const char *entry = *pathspec;
113 const char **p;
114 int prefixlen;
115
116 if (!prefix && !entry)
117 return NULL;
118
119 if (!entry) {
120 static const char *spec[2];
121 spec[0] = prefix;
122 spec[1] = NULL;
123 return spec;
124 }
125
126 /* Otherwise we have to re-write the entries.. */
127 p = pathspec;
128 prefixlen = prefix ? strlen(prefix) : 0;
129 do {
130 *p = prefix_path(prefix, prefixlen, entry);
131 } while ((entry = *++p) != NULL);
132 return (const char **) pathspec;
133}
134
135/*
136 * Test if it looks like we're at a git directory.
137 * We want to see:
138 *
139 * - either a objects/ directory _or_ the proper
140 * GIT_OBJECT_DIRECTORY environment variable
141 * - a refs/ directory
142 * - either a HEAD symlink or a HEAD file that is formatted as
143 * a proper "ref:", or a regular file HEAD that has a properly
144 * formatted sha1 object name.
145 */
146static int is_git_directory(const char *suspect)
147{
148 char path[PATH_MAX];
149 size_t len = strlen(suspect);
150
151 strcpy(path, suspect);
152 if (getenv(DB_ENVIRONMENT)) {
153 if (access(getenv(DB_ENVIRONMENT), X_OK))
154 return 0;
155 }
156 else {
157 strcpy(path + len, "/objects");
158 if (access(path, X_OK))
159 return 0;
160 }
161
162 strcpy(path + len, "/refs");
163 if (access(path, X_OK))
164 return 0;
165
166 strcpy(path + len, "/HEAD");
167 if (validate_headref(path))
168 return 0;
169
170 return 1;
171}
172
173static int inside_git_dir = -1;
174
175int is_inside_git_dir(void)
176{
177 if (inside_git_dir >= 0)
178 return inside_git_dir;
179 die("BUG: is_inside_git_dir called before setup_git_directory");
180}
181
182static int inside_work_tree = -1;
183
184int is_inside_work_tree(void)
185{
186 if (inside_git_dir >= 0)
187 return inside_work_tree;
188 die("BUG: is_inside_work_tree called before setup_git_directory");
189}
190
191static char *gitworktree_config;
192
193static int git_setup_config(const char *var, const char *value)
194{
195 if (!strcmp(var, "core.worktree")) {
196 if (gitworktree_config)
197 strlcpy(gitworktree_config, value, PATH_MAX);
198 return 0;
199 }
200 return git_default_config(var, value);
201}
202
203const char *setup_git_directory_gently(int *nongit_ok)
204{
205 static char cwd[PATH_MAX+1];
206 char worktree[PATH_MAX+1], gitdir[PATH_MAX+1];
207 const char *gitdirenv, *gitworktree;
208 int wt_rel_gitdir = 0;
209
210 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
211 if (!gitdirenv) {
212 int len, offset;
213
214 if (!getcwd(cwd, sizeof(cwd)-1))
215 die("Unable to read current working directory");
216
217 offset = len = strlen(cwd);
218 for (;;) {
219 if (is_git_directory(".git"))
220 break;
221 if (offset == 0) {
222 offset = -1;
223 break;
224 }
225 chdir("..");
226 while (cwd[--offset] != '/')
227 ; /* do nothing */
228 }
229
230 if (offset >= 0) {
231 inside_work_tree = 1;
232 git_config(git_default_config);
233 if (offset == len) {
234 inside_git_dir = 0;
235 return NULL;
236 }
237
238 cwd[len++] = '/';
239 cwd[len] = '\0';
240 inside_git_dir = !prefixcmp(cwd + offset + 1, ".git/");
241 return cwd + offset + 1;
242 }
243
244 if (chdir(cwd))
245 die("Cannot come back to cwd");
246 if (!is_git_directory(".")) {
247 if (nongit_ok) {
248 *nongit_ok = 1;
249 return NULL;
250 }
251 die("Not a git repository");
252 }
253 setenv(GIT_DIR_ENVIRONMENT, cwd, 1);
254 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
255 if (!gitdirenv)
256 die("getenv after setenv failed");
257 }
258
259 if (PATH_MAX - 40 < strlen(gitdirenv)) {
260 if (nongit_ok) {
261 *nongit_ok = 1;
262 return NULL;
263 }
264 die("$%s too big", GIT_DIR_ENVIRONMENT);
265 }
266 if (!is_git_directory(gitdirenv)) {
267 if (nongit_ok) {
268 *nongit_ok = 1;
269 return NULL;
270 }
271 die("Not a git repository: '%s'", gitdirenv);
272 }
273
274 if (!getcwd(cwd, sizeof(cwd)-1))
275 die("Unable to read current working directory");
276 if (chdir(gitdirenv)) {
277 if (nongit_ok) {
278 *nongit_ok = 1;
279 return NULL;
280 }
281 die("Cannot change directory to $%s '%s'",
282 GIT_DIR_ENVIRONMENT, gitdirenv);
283 }
284 if (!getcwd(gitdir, sizeof(gitdir)-1))
285 die("Unable to read current working directory");
286 if (chdir(cwd))
287 die("Cannot come back to cwd");
288
289 /*
290 * In case there is a work tree we may change the directory,
291 * therefore make GIT_DIR an absolute path.
292 */
293 if (gitdirenv[0] != '/') {
294 setenv(GIT_DIR_ENVIRONMENT, gitdir, 1);
295 gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
296 if (!gitdirenv)
297 die("getenv after setenv failed");
298 if (PATH_MAX - 40 < strlen(gitdirenv)) {
299 if (nongit_ok) {
300 *nongit_ok = 1;
301 return NULL;
302 }
303 die("$%s too big after expansion to absolute path",
304 GIT_DIR_ENVIRONMENT);
305 }
306 }
307
308 strcat(cwd, "/");
309 strcat(gitdir, "/");
310 inside_git_dir = !prefixcmp(cwd, gitdir);
311
312 gitworktree = getenv(GIT_WORK_TREE_ENVIRONMENT);
313 if (!gitworktree) {
314 gitworktree_config = worktree;
315 worktree[0] = '\0';
316 }
317 git_config(git_setup_config);
318 if (!gitworktree) {
319 gitworktree_config = NULL;
320 if (worktree[0])
321 gitworktree = worktree;
322 if (gitworktree && gitworktree[0] != '/')
323 wt_rel_gitdir = 1;
324 }
325
326 if (wt_rel_gitdir && chdir(gitdirenv))
327 die("Cannot change directory to $%s '%s'",
328 GIT_DIR_ENVIRONMENT, gitdirenv);
329 if (gitworktree && chdir(gitworktree)) {
330 if (nongit_ok) {
331 if (wt_rel_gitdir && chdir(cwd))
332 die("Cannot come back to cwd");
333 *nongit_ok = 1;
334 return NULL;
335 }
336 if (wt_rel_gitdir)
337 die("Cannot change directory to working tree '%s'"
338 " from $%s", gitworktree, GIT_DIR_ENVIRONMENT);
339 else
340 die("Cannot change directory to working tree '%s'",
341 gitworktree);
342 }
343 if (!getcwd(worktree, sizeof(worktree)-1))
344 die("Unable to read current working directory");
345 strcat(worktree, "/");
346 inside_work_tree = !prefixcmp(cwd, worktree);
347
348 if (gitworktree && inside_work_tree && !prefixcmp(worktree, gitdir) &&
349 strcmp(worktree, gitdir)) {
350 inside_git_dir = 0;
351 }
352
353 if (!inside_work_tree) {
354 if (chdir(cwd))
355 die("Cannot come back to cwd");
356 return NULL;
357 }
358
359 if (!strcmp(cwd, worktree))
360 return NULL;
361 return cwd+strlen(worktree);
362}
363
364int git_config_perm(const char *var, const char *value)
365{
366 if (value) {
367 int i;
368 if (!strcmp(value, "umask"))
369 return PERM_UMASK;
370 if (!strcmp(value, "group"))
371 return PERM_GROUP;
372 if (!strcmp(value, "all") ||
373 !strcmp(value, "world") ||
374 !strcmp(value, "everybody"))
375 return PERM_EVERYBODY;
376 i = atoi(value);
377 if (i > 1)
378 return i;
379 }
380 return git_config_bool(var, value);
381}
382
383int check_repository_format_version(const char *var, const char *value)
384{
385 if (strcmp(var, "core.repositoryformatversion") == 0)
386 repository_format_version = git_config_int(var, value);
387 else if (strcmp(var, "core.sharedrepository") == 0)
388 shared_repository = git_config_perm(var, value);
389 return 0;
390}
391
392int check_repository_format(void)
393{
394 git_config(check_repository_format_version);
395 if (GIT_REPO_VERSION < repository_format_version)
396 die ("Expected git repo version <= %d, found %d",
397 GIT_REPO_VERSION, repository_format_version);
398 return 0;
399}
400
401const char *setup_git_directory(void)
402{
403 const char *retval = setup_git_directory_gently(NULL);
404 check_repository_format();
405 return retval;
406}